Carbon and oxygen isotope record and sedimentology/facies across selected time slices in the Mid Paleozoic in Vietnam

泥盆纪是气候长期动态变化和生物多样性发生重大变化的时期。中泥盆世陆地植物的迅速增加，伴随着大气CO2值在泥盆纪末期从4000ppm迅速下降到现在的约350ppm。珊瑚礁生态系统在弗拉斯尼亚/法门期(F/F)大灭绝事件中于弗拉斯尼期晚期灭绝。这一事件是中古生代与其他事件并列的五大物种灭绝事件之一。大多数对大规模灭绝事件的研究都位于瑞克海周围，而其他地区，如古特提斯地区，记录仍然很少。我们在这个项目中的目标是使用地球化学指标来评估与盆地环境(越南北部和南部的剖面)中古生代重要物种灭绝有关的缺氧事件的存在，并将结果与亚洲其他地区的已知数据进行比较，特别是与南中国的数据。这一结果将有助于更好地了解气候变化，并将改善泥盆纪和石炭纪的碳同位素地层学。

The Devonian was a time of dynamic long-term climate change and substantial changes in biodiversity. The rapid rise of land plants during the Middle Devonian was coupled with rapidly decreasing atmospheric CO2 values from 4000 ppm to nearly present day values of about 350 ppm during the latest Devonian. Reef ecosystems became extinct in the late Frasnian during the Frasnian/Famennian (F/F) mass extinction event. This event is one of the Big Five extinction events beside other events in the mid-Paleozoic. Most studies of mass extinction events are located around the Rheic Ocean, while other areas such as the Paleo-Tethys remain poorly documented. Our goal in this project is to use geochemical proxies to evaluate the presence of anoxic events associated with important extinctions in the mid-Paleozoic in basinal settings (sections in northern and southern Vietnam) and to compare the results with known data from elsewhere in Asia, particularly with South China. The results will contribute to a better understanding of climate variations and will improve carbon isotope stratigraphy of the Devonian and the Carboniferous.